Pulse oximeters are medical devices commonly used in the healthcare industry to measure the oxygen saturation levels in the blood non-invasively. A pulse oximeter can indicate the percent oxygen saturation and the pulse rate of the user.
Pulse oximeters can be used for many different reasons. For example, a pulse oximeter can be used to monitor an individual's pulse rate during physical exercise. An individual with a respiratory condition or a patient recovering from an illness or surgery can wear a pulse oximeter during exercise in accordance with a physician's recommendations for physical activity. Individuals also can use a pulse oximeter to monitor oxygen saturation levels to ensure adequate oxygenation, for example, during flights or during high-altitude exercising.
Modern pulse oximeters, for example, can include a peripheral probe and a microprocessor unit to display a waveform, oxygen saturation and pulse rate. The probe can be placed in contact with an appropriate part of the individual (e.g., a finger). The probe can include multiple light emitting devices such as LEDs, one in the visible red part of the spectrum (e.g., 660 nm) and one in the infrared part of the spectrum (e.g., 940 nm). The beams of light pass through the tissues to one or more photodetectors. The amount of light absorbed by blood and soft tissues depends on the concentration of hemoglobin, and the amount of light absorption at each frequency depends on the degree of oxygenation of the hemoglobin within the tissues.
A variety of types of pulse oximeters are known. However, some of these devices are not particularly convenient to use and can cause discomfort when worn.